Short Specifiations
Simplifies calibration/verification of precision calibrators and current
sources
Shunts sized for currents from 1mA to 100A
Usable from dc to 100 kHz
14 individual dc and ac current shunts with a 1, 2, 5 sequence over
6 decades of current
Simple direct measurements, making ac/dc transfers unnecessary
Stability typically better then ± 5.0 µOhm/Ohm for one year
Typical angular accuracy of better than ± 0.003º at 1 kHz
Application:
The wide range of shunt values permit measuring from 0.1mA to 100
Amps.
The physical construction and the components used in the current
shunts ensure that the frequency response is very flat (amplitude
displacement error relative to dc resistance).
Also the phase displacement at 100 kHz is small enough to be
neglected in all but the highest accuracy measurements.
Combined with excellent dc resistance stability, the shunts can be
used to directly measure current through their full bandwidth.
This simplifies precision ac current measurements as the complex
ac/dc transfer measurement process will no longer be necessary for
many precision current measurement applications.
These characteristics make the A40B shunts ideal for traditional
precision current applications such as calibrator verification.
Also, the wide current range allows verification of high current
transconductance amplifiers.
The low phase shift error is critical for measurement of non-sinusoidal
wave shapes, as found in power quality or sampling digital
wattmeter measurement applications.
Technical overview
The shunts come in four different sizes. The full set includes:
four fully enclosed dc and ac current shunts: 1 mA, 10 mA, 20 mA,
50 mA
five small size radial dc and ac current shunts: 100 mA, 200 mA, 500
mA, 1 A, 2 A
three medium size radial dc and ac current shunts: 5A, 10 A, 20 A
two large size radial dc and ac current shunts: 50 A, 100 A
Voltage output is nominally 0.8 volts for the nominal rated current
input.
The output is measured by a voltmeter or detector, such as precision
voltmeters, ac measurement standards, ac/dc transfer standards,
or thermal voltage converters, fitting them to a wide variety of
metrology applications.
The radial style dc and ac current shunt design gives high
performance with minimum external magnetic fields.
Plus, the open nature of the physical design maximizes air flow so the
shunts have a minimal power coefficient effects.
This permits each shunt to be used over a wide range of currents
with stable resistance characteristics.
The shunt resistance is designed to minimize interaction with the
detector instrumentation.
The 100 Amp shunt resistance is 8 milliohms, with shunt resistance
increasing to 80 ohms for the 10 mA shunt. Additionally, the 1mA
shunt includes an internal battery operated buffer amplifier.
It drives the output voltage so the 800 ohm shunt resistance has
minimal interaction with the measurement device.